Commit 1df9d1d4 authored by Lars-Peter Clausen's avatar Lars-Peter Clausen Committed by Jonathan Cameron
Browse files

staging:iio:ad7291: Rework regulator handling 



Add platform_data for the driver which allows to specify whether an external
reference voltage is used or not. It is not possible to use the return value of
regulator_get() for this since the regulator framework is able to return a dummy
regulator in case no regulator has been specified. In this case the driver will
always get a valid regulator, no matter if it has been specified or not.  Also
make the regulator non-optional if platform_data states that an external
reference voltage should be used.

Signed-off-by: default avatarLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
parent 88198d2b

drivers/staging/iio/adc/ad7291.c

+23 −15
Original line number Diff line number Diff line
@@ -21,6 +21,8 @@ 
#include <linux/iio/sysfs.h>

#include <linux/iio/events.h>



#include "ad7291.h"



/*

 * Simplified handling

 *
@@ -76,7 +78,6 @@ 
struct ad7291_chip_info {

	struct i2c_client	*client;

	struct regulator	*reg;

	u16			int_vref_mv;

	u16			command;

	u16			c_mask;	/* Active voltage channels for events */

	struct mutex		state_lock;
@@ -445,7 +446,15 @@ static int ad7291_read_raw(struct iio_dev *indio_dev, 
	case IIO_CHAN_INFO_SCALE:

		switch (chan->type) {

		case IIO_VOLTAGE:

			*val = chip->int_vref_mv;

			if (chip->reg) {

				int vref;

				vref = regulator_get_voltage(chip->reg);

				if (vref < 0)

					return vref;

				*val = vref / 1000;

			} else {

				*val = 2500;

			}

			*val2 = AD7291_BITS;

			return IIO_VAL_FRACTIONAL_LOG2;

		case IIO_TEMP:
@@ -513,9 +522,10 @@ static const struct iio_info ad7291_info = { 
static int ad7291_probe(struct i2c_client *client,

		const struct i2c_device_id *id)

{

	struct ad7291_platform_data *pdata = client->dev.platform_data;

	struct ad7291_chip_info *chip;

	struct iio_dev *indio_dev;

	int ret = 0, voltage_uv = 0;

	int ret = 0;



	indio_dev = iio_device_alloc(sizeof(*chip));

	if (indio_dev == NULL) {
@@ -524,12 +534,14 @@ static int ad7291_probe(struct i2c_client *client, 
	}

	chip = iio_priv(indio_dev);



	chip->reg = regulator_get(&client->dev, "vcc");

	if (!IS_ERR(chip->reg)) {

	if (pdata && pdata->use_external_ref) {

		chip->reg = regulator_get(&client->dev, "vref");

		if (IS_ERR(chip->reg))

			goto error_free;



		ret = regulator_enable(chip->reg);

		if (ret)

			goto error_put_reg;

		voltage_uv = regulator_get_voltage(chip->reg);

	}



	mutex_init(&chip->state_lock);
@@ -542,12 +554,8 @@ static int ad7291_probe(struct i2c_client *client, 
			AD7291_T_SENSE_MASK | /* Tsense always enabled */

			AD7291_ALERT_POLARITY; /* set irq polarity low level */



	if (voltage_uv) {

		chip->int_vref_mv = voltage_uv / 1000;

	if (pdata && pdata->use_external_ref)

		chip->command |= AD7291_EXT_REF;

	} else {

		chip->int_vref_mv = 2500; /* Build-in ref */

	}



	indio_dev->name = id->name;

	indio_dev->channels = ad7291_channels;
@@ -590,12 +598,12 @@ static int ad7291_probe(struct i2c_client *client, 
	if (client->irq)

		free_irq(client->irq, indio_dev);

error_disable_reg:

	if (!IS_ERR(chip->reg))

	if (chip->reg)

		regulator_disable(chip->reg);

error_put_reg:

	if (!IS_ERR(chip->reg))

	if (chip->reg)

		regulator_put(chip->reg);



error_free:

	iio_device_free(indio_dev);

error_ret:

	return ret;
@@ -611,7 +619,7 @@ static int ad7291_remove(struct i2c_client *client) 
	if (client->irq)

		free_irq(client->irq, indio_dev);



	if (!IS_ERR(chip->reg)) {

	if (chip->reg) {

		regulator_disable(chip->reg);

		regulator_put(chip->reg);

	}

drivers/staging/iio/adc/ad7291.h

0 → 100644
+12 −0
Original line number Diff line number Diff line 
#ifndef __IIO_AD7291_H__

#define __IIO_AD7291_H__



/**

 * struct ad7291_platform_data - AD7291 platform data

 * @use_external_ref: Whether to use an external or internal reference voltage

 */

struct ad7291_platform_data {

	bool use_external_ref;

};



#endif